SANTO DOMINGO, Dominican Republic (AP) - Kansas City Royals pitcher Yordano Ventura and former major leaguer Andy Marte died in separate traffic accidents early Sunday in their native Dominican Republic.

Highway patrol spokesman Jacobo Mateo said Ventura died on a highway leading to the town of Juan Adrian, about 40 miles (70 kilometers) northwest of Santo Domingo. He said it was not clear if Ventura was driving.

Metropolitan traffic authorities said they had opened an investigation into the crash, as well as that of Marte, who died when the Mercedes Benz he was driving hit a house along a road between San Francisco de Macoris and Pimentel, about 95 miles (150 kilometers) north of the capital.

Traffic authority spokesman Diego Pesqueira told The Associated Press there were no rains registered at the time of Ventura's accident but that it is often foggy in the early morning. He added that the vehicle's tires were in good condition and experts think the cause of the accident was speeding. The official results of the investigation will be released in the coming days.

The country, whose roads are among the world's most dangerous, has now lost four current or former major leaguers to traffic accidents in recent years.

President Danilo Medina posted tweets saying the nation "is dressed in mourning with the deaths of Andy Marte and Yordano Ventura, great sportsmen who raised high our national banner."

Ventura, 25, burst onto the baseball scene with a 100 mph fastball and an explosive attitude to match. He was a fierce competitor always willing to challenge hitters inside, then deal with the ramifications when they decided to charge the mound.

He went 14-10 with a 3.20 ERA in 2014, his first full season in the big leagues, and the next year he helped the long-downtrodden Royals reach the World Series for the first time since 1985. He proceeded to dominate San Francisco in both of his starts, though the Royals would ultimately lose in seven games.

"Our prayers right now are with Yordano's family as we mourn this young man's passing," Royals general manager Dayton Moore said in a statement. "He was so young and so talented, full of youthful exuberance and always brought a smile to everyone he interacted with. We will get through this as an organization, but right now is a time to mourn and celebrate the life of Yordano."

Born June 3, 1991, in Samana, Dominican Republic, Ventura quit school at 14 and was laboring on a construction crew to support his family when he heard about a tryout, which led to a spot in the Royals' academy on the island.

The right-handed Ventura went 11-12 with a 4.45 ERA last season, and wound up pitching his entire career for the Royals, going 38-31 with a 3.89 ERA.

Fans began arriving at Kauffman Stadium shortly after Ventura's death was announced, leaving flowers, hats and other mementos outside the stadium. Flags outside the ballpark also were lowered to half-staff.

Marte, a 33-year-old infielder, played in the Major Leagues from 2005-2010 with Atlanta and Cleveland and returned in 2014 with Arizona. He hit .218 with 21 home runs and 99 RBIs in the big leagues. He spent the last two seasons in South Korea, where he hit 22 homers last year.

Both Ventura and Marte were part of the Dominican winter league team Aguilas Cibaenas, though neither was playing this season.

"We have awoken this Sunday with this sad news that we have lost a special being," club president Winston Llenas said in a statement about Marte that was issued before Ventura's death became known.

Ventura is the second young star pitcher to die in past four months. Marlins ace Jose Fernandez, 24, was among three men killed in a boating accident in September.

Two other active Dominican baseball players have died on the country's dangerous highways in recent years.

St. Louis Cardinal outfielder Oscar Taveras - a close friend of Ventura - died in 2014 when he crashed in his hometown of Puerto Plata. He was 22. Shortstop Andujar Cedeno died at age 31 in a 2000 crash in the city of La Romana.

A 2015 study by the World Health Organization found that the Dominican Republic had the highest traffic accident death rate in the Americas, with a rate of 29.3 per 100,000 inhabitants.

Marte's family was holding a vigil for him on Sunday and planned to bury him within hours. Ventura's remains were still at a coroner's office in the city of Santiago.

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